Refrigeration evaporators



y 1964 J. R. FERGUSON ammmnon EVAPORATORS Filed Feb. 6, 1962 2 Shuts-Sheet 1 FIG.3

FIG. I

diff/II I'Nvnvron Jmv Ross FERGUSON V flr-r-oRM'rs July 28, 1964 J. R. FERGUSON REFRIGERATION summons 2 Sheets-Sheet 2 Filed Feb. 6, 1962 FIG.4

I VEN fOR Jbmv' Ron linear/401v United States Patent 3,142,163 REFRIGERATION EVAPORATORS John Ross Ferguson, Dundee, Scotland, assignor to Morphy-Richards (Astral) Limited Filed Feb. 6, 1962, Ser. No. 171,462 8 Claims. (Cl. 62-517) This invention relates to domestic refrigerators of the type incorporating absorption refrigerating apparatus which uses inert gas, the evaporator of the refrigerative apparatus being used both for freezing purposes and for cooling the cool chamber of the refrigerator.

It is an object of the invention to provide a refrigerator of the type defined above, having a freezing compartment of relatively large capacity suitable (for example) for the storage of frozen foods.

In accordance with the invention a refrigerator of the type defined includes a freezing chamber formed by a casing enclosing the evaporator, the said casing including a portion which extends downwardly below the evaporator to form an additional storage compartment whose contents will be cooled by convection currents of cold air from the evaporator.

The nature of the invention, whose scope is particularly defined in the appended claims, will sufiiciently appear from the following description of a preferred form thereof as applied to a refrigerator of known construction. The preferred form of the invention is illustrated in the accompanying drawings, in which:

FIGURE 1 is a part sectional side elevational of the refrigerator;

FIGURE 2 is a sectional side elevation, on a larger scale of part of the refrigerator shown in FIGURE 1;

FIGURE 3 is a View on the line III-III of FIGURE 2;

FIGURE 4 is a view on the line IV1V of FIGURE 3; and

FIGURE 5 is an isometric View of a liner shown in the other figures.

The refrigerator shown in the drawings comprises in known manner a heat insulated outer casing enclosing a cool chamber 11. The refrigerative apparatus of the refrigerator is located behind the rear wall 12 of the cool chamber, and the evaporator 14 of this apparatus is constituted by a length of tubing which projects forwardly through an opening or window 15 in the rear wall 12, the tubing being bent in a horizontal plane to provide four parallel, forwardly extending limbs 16, 17, 18 and 19 connected in series. The arrangement is such that the refrigerant flows first through the two inner limbs 17 and 18, which thus form the lower temperature part of the evaporator, and thereafter through the two outer limbs 16 and 19. A metal cold plate 20 rests on top of the inner pair of limbs and is secured in metallic contact with them, but is not in direct metallic contact with the outer pair of limbs, this cold plate forming the floor of a freezing compartment 21. The top, back and side walls of this compartment 21. The top, back and side walls of this compartment are formed by a sheet metal casing 22 of generally tubular form which is supported upon the outer limbs 16 and 19 of the evaporator 14 and is in metallic contact with them, but is not in direct metallic contact with the inner limbs 17 and 18 or with the plate 20. The casing 22 is fitted to the evaporator 14 after the latter has been passed through the above mentioned window 15, inwardly facing channels 24 and 25 on the side walls of the casing 22 sliding rearwardly onto the outer limbs 16 and 19 of the evaporator. The front end of the casing is closed by a door 23.

The freezing compartment 21 serves satisfactorily for the production of ice and/ or the storage of frozen foods, provided that the ice trays or food packages rest directly 3,142,163 Patented July 28, 1964 on the cold plate 20. However, the effective capacity of the freezing compartment cannot be increased by merely increasing its height to accommodate two or more layers of packages, since the packages in an upper layer are not sufiiciently cooled by conduction through the packages of the lower layer, while the top and side Walls of the casing 22 (being in contact with only the outer, higher temperature limbs 16 and 19 of the evaporator and being exposed on their outer surfaces to the atmosphere of the cool chamber 11) are not at a sufiiciently low temperature to eflect the required cooling.

In accordnace with a primary feature of the present invention, the casing 22 is extended downwardly so as to enclose below the evaporator 14 a space which forms a supplementary freezing chamber 26, the contents of this chamber being effectively cooled by air flowing downwardly by convection from the inner, lower temperature limbs 17, 18 of the evaporator.

The supplementary freezing chamber 26 is provided with means of some kind for preventing excessive conduction of heat between the articles in the chamber 26 and the metallic casing 22.

This means comprises a liner 27 of heat insulating material, for example synthetic resin sheet material. The liner 27, which is most clearly seen in FIGURE 5, is of substantially channel shaped cross-section, with its sides 28 and 29 extending upwardly, and is reduced in wallthickness at its corners 30 and 31. On its outer surfaces the liner is integrally formed with ribs 32.

The liner 27 fits closely against the side and bottom walls of the casing 22 within the freezing chamber 26, its sides 28, 29 being held vertical by the sides of the casing. The ribs 32 hold the liner spaced over the greater part of its surface from the metallic casing.

In an alternative arrangement the liner 27 is dispensed with, and the floor (and possibly also the side walls) of the chamber 26 is formed with small isolated projections so that goods stored in the chamber will be in contact only with the projections and over the greater part of their surfaces will be held spaced by a layer of air from the material of the casing 22.

This and other variations will of course be possible within the scope of the invention as defined in the appended claims.

I claim:

1. In a refrigerator of the type defined including an evaporator comprising a metal tube bent to form a first evaporator section and a second evaporator section, said sections being connected in series for the flow of refrigerant through said first section and then through said second section, said second section including two horizontal parallel limbs embracing said first section: a casing of tubular metal construction supported along its sides on said two limbs to enclose said evaporator, said casing being shaped and dimensioned to form above said first evaporator section a chamber for the reception of goods to be supported on said first section, and to form below said first section an additional chamber for the reception of goods which will be cooled by convection currents of cold air from said first section.

2. A combination according to claim 1, further comprising a lining of heat insulating material in said additional chamber for reducing surface contact between goods placed in said additional chamber and said casing.

3. In a refrigerator of the type defined, including an evaporator formed by a metal tube bent in a horizontal plane to have at least four substantially parallel limbs connected in series for the flow of refrigerant first through the inner pair of limbs and then through the outer pair of limbs: a tubular metal casing extending longtiudinally of said limbs and supported at its sides on said outer pair of limbs in metallic contact therewith, said outer limbs affording the sole means of metallic contact between casing and the inner pair of limbs, said casing being shaped and dimensioned to form an upper chamber above said evaporator and a lower chamber below said evaporator, a metal plane secured in metallic contact with said inner pair of limbs and held spaced thereby from said outer pair of limbs and from said casing, said plate being adapted to support goods stored in said upper chamber and to cool said goods by contact therewith, and a lining of heat insulating material in said lower chamber to prevent contact between the walls of said casing bounding said lower chamber and goods stored in the lower chamber to be cooled by convection currents of cold air from the said evaporator.

4. In a refrigerator of the type defined; an evaporator having an inner evaporator section and an outer evapo rator section, said inner and outer sections lying in the same horizontal plane and being connected in series for the flow of refrigerant firstly through the inner section and then through the outer section, a casing enclosing at least said inner section, said casing being in thermally conductive contact withsaid outer section and spaced from said inner section, said casing being shaped and dimensioned to form above said inner evaporator section a chamber for the reception of goods to be supported on said inner section and to form below said inner section an additional chamber for the reception of goods which will be cooled by convection currents of cold air from said inner section.

5. In a refrigerator of the type defined; an evaporator having an inner evaporator section and an outer evaporator section, said inner and outer sections lying in the same horizontal plane and being connected in series for the how of refrigerant firstly through the inner section and then through the outer section, a metal casing enclosing at least said inner section, said metal casing being supported on and in thermally conductive contact with said outer section and spaced from said inner section,

4 said metal casing being shaped and dimensioned to form above said inner evaporator section a chamber for the reception of goods to be supported on said inner section and to form below said inner section an additional chamber for the reception of goods which will be cooled by convection currents of cold air from said inner section, and said casing being disposed in an upper part of the main storage volume of the refrigerator, thereby to cool said main storage volume. v

6. In a refrigerator of the type defined; an evaporator having an inner evaporator section and an outer evaporator section, said inner and outer sections lying in the same horizontal plane and being connected in series for the flow of refrigerant firstly through the inner section and then through the outer section, a casing enclosing at leastsaid inner section, said casing being in thermally conductive contact with said outer section and spaced from said inner section, said casing being shaped and dimensioned to form below said inner section a chamber for the reception of goods which will be cooled by convection currents of cold air from said inner section.

7. In a refrigerator of the type defined, an evaporator according to claim 6 wherein said outer evaporator section substantially surrounds said inner evaporator section in said horizontal plane.

8. In a refrigerator of the type defined, an evaporator according to claim 4 wherein said outer evaporator section substantially surrounds said inner evaporator section in said horizontal plane.

References Cited in the file of this patent UNITED STATES PATENTS 2,045,048 Newill June 23, 1936 2,274,967 Nelson Mar. 3, 1942 2,301,313 Money Nov. 10, 1942 2,325,706 Philipp Aug. 3, 1943 2,633,003 Jordan Mar. 31, 1953 

1. IN A REFRIGERATOR OF THE TYPE DEFINED INCLUDING AN EVAPORATOR COMPRISING A METAL TUBE BENT TO FORM A FIRST EVAPORATOR SECTION AND A SECOND EVAPORATOR SECTION, SAID SECTIONS BEING CONNECTED IN SERIES FOR THE FLOW OF REFRIGERANT THROUGH SAID FIRST SECTION AND THEN THROUGH SAID SECOND SECTION, SAID SECOND SECTION INCLUDING TWO HORIZONTAL PARALLEL LIMBS EMBRACING SAID FIRST SECTION: A CASING OF TUBULAR METAL CONSTRUCTION SUPPORTED ALONG ITS SIDES ON SAID TWO LIMBS TO ENCLOSE SAID EVAPORATOR, SAID CASING BEING SHAPED AND DIMENSIONED TO FORM ABOVE SAID FIRST EVAPORATOR SECTION A CHAMBER FOR THE RECEPTION OF GOODS TO BE SUPPORTED ON SAID FIRST SECTION, AND TO FORM BELOW SAID FIRST SECTION AN ADDITIONAL CHAMBER FOR THE RECEPTION OF GOODS WHICH WILL BE COOLED BY CONVECTION CURRENTS OF COLD AIR FROM SAID FIRST SECTION. 